I try to use upgrade app to upgrade, but the app tell me I can upgrade 13.10 directly. But, if I press upgrade button, then the error message occured like...
An upgrade from 'quantal' to 'saucy' is not supported with this tool.
So, I try to upgrade with terminal by
but, same error message occured. I using 12.10 now. I want to upgrade to 13.10, but I can't upgrade 13.10, and 13.04.
------add------ I installed ubuntu 12.04 with Windows Installer, and I upgraded this to 12.10.